Cellulose-ether solvent and composition



' vents.

ing arts.

' chlorethylene, it" hasbeen found that such Patented Apr. 3, 1923.

0 FE CE STEWART J. CARROLL, OF ROCHESTER, NEW YORK, ASSIGNOR TO EASTMAN 'KOiDAK COMPANY, OF ROCHESTER, NEW YORK, AOORPORATION or NEW YORK.

CELLULOSE-ETHER SOLVENT AND COMPOSITION.

r10 Drawing.

To (all whom it may concern:

Be it known that I, STEWART J. CARROLL, a citizen of the United States of America, residing at Rochester, in the county of Monroe and State'of New York, have invented certain new and useful Improvements in Cellulose-Ether Solvents and Compositions, of which the following is a full, clear, and exact specification.

This invention relates to solvents for making strong solutions of cellulose ether and also relates to the cellulose ether compositions produced by the aid of such sol- One object of my invention is to provide a solvent which will dissolve such large proportions of cellulose ethers that thick or viscous flowable solutions may be Obtained for use in plastic and film mak- Another object of my invention is to provide a cellulose ether solution which may be manufactured into strong, flexible, transparent film on the machines and by the methods now in use.

In U. S. Patent No. 1,188,37 6-, Lilienfeld,

June 20, 1916, there are disclosed a series of alkyl ethers of cellulose. Certain of these are practically insoluble in water, and my invention relates, but is not limited, to the ethers having that roperty. While the ethers' form thin so utions in the lower monohydroxy aliphatic alcohols or persingle solvents by themselves do not dissolve a sufiicient proportion of the others to make a desirable thick flow able composition or dope, such as'maybe used in the manufacture. of photographic film base'by customary methods, or in the other plastic arts.

.I have discovered. that an adequately strong and useful solvent'may be prepared by mixing1 perchlorethylene with one'or more of t ev to parts of perchlorethylene" and 10 to 50 parts b weight of thealcohol, say methyl or ethy alcohol as an illustrationlf In the preferred form of my invention,I use equal parts by weight of perchlorethylene and methyl or ethyl alcohol. While the amount of ether that may be dissolved in such mixed solvents maybe varied as desired over a Application filed may 24,

lower monohydroxy aliphatic. alcohols. For example, I may use from-90;

1921. Serial No. 472,270.

ample, that 1 part by weight ofwater-insoluble ethyl cellulose when dissolved in 5 parts of one of the above mixed or compound solvents yields a thick viscous flowa'ble solution.

Other substances which impart additional 'suppleness, or incombustibility, or other qualities, to the film may also be added to the dope, such, for instance, as triphenyl: or trlcresyl phosphate, camphor, etc. In the formation of the'film a considerable amount of perchlorethylene is left therein, due to its relatively low volatility. It imparts useful properties tosuch film.

The ingredients are of the ordinary commerclal type and sufiiciently purified for the process of filmmanufacture, so as to give a dope yielding films havin the proper "relative freedom from color. 'lhe viscousliowable dope above described can be used in connection with the usual film forming apparatus without the necessity ofexpensave alterations in the latter. By lower monohydroxy aliphatic alcohol I include one having less than six carbon atoms.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

'1. A composition of matter, comprising cellulose ether dissolved in a mixture contaming perchlorethylene and a lower monohydroxy aliphati'caalcohol.

2. A viscous flowa'ble composition, comprising an alkyl ether of cellulose dissolved 'chl'o'rethylene;

6, As an article of manufacture, a deposited or flowed flexible film containing cellulose etherand perchloreth ylene.

Signed at Rochester, New 1 day of .May 1921.

STEWART J. CARROLL.

ork, this 14th sition of matter comprising 

